Improvement in locks



@sind @ibitza CHARLES O. DIOKERMAN, OF BOSTON, MASSACHUSETTS.

Letters Patent No. 101,355, :lated March 29, 1870.

IMPRQVBMENT 1N LOCKS.

The Schedule referred to in these Letters Patent and making part of thesame.

To all whom it may concern:

Be it known that I, CHARLns C. DICKERMAN, of Boston, in the county ofSuffolk and State of .Massachusetts, have invented Improvements inLocks; and I do hereby declare that the following, taken in connectionwith the drawings which accompany and form part of this specication, isa description of my in- `vention snffcientto enable those skilled in theart to practice it.

One part of this invention consists in converting a mortise or rim lockinto a drawer or cabinetlock, by simply changing the covers, so as toadapt the lock either for use .upon the outside of a door as a rim lock,or so that it can be inserted in the manner of a drawer-lock in thematerial of the drawer or door to which the lock is applied.

Figures 1 and 2 are plans showing the same lock in the conditionsproduced by having the bolt thrown outward by different keys, thisresulting simply in changing the position of the stops a and b, whichoperate in combination with the tumblers c and d;

AFigure 3 is a plan of the lock-case, with the mechanism removed;

Figure 4 is a reversed plan of the box-cover Figure 5 is a reversed planof the plate-cover;

Figure 6 is a plan, and

Figure :7 'an end view of' the bolt, with the adjustable stops c andV bFigure 8'is a plan of the lower tumbler, which operates in conjunctionwith a stop, e,'on the bolt;

Figures 9 and 10 are, respectively, plans of the tumblers d and c; l

Figure 11 shows the key used in throwing the bolt in iig. l; and

Figure 12 shows the key used in throwing the bolt in iig. 2.

The bolt f has a slot, which, working on the pin y of the case, guidesit under the action ofthe key working between the jaws h h' ofthe bolt.

The stops a, b are elevated on springs, i, so as to pass over the lowertumhlerj, and are confined in position by the screw k, which passesthrough a washer, l, and venters nut-threads in the bolt, so as to clampthe stops to the bolt and prevent accidental movement of them',permitting them, however, to move laterally by force exerted on them bythe key through the tumblers, the stops being slotted where the screwpasses through them.

I am aware a fliction spring has been used, when rigidly attached to theinside of the cap o r cover, so as to press upon thestops, and hence Ido not claim, broadly, the use of the friction spring for holding inplace the stops. My spring is placed on the bolt f, and necessarilymoves with the holt, and therefore occupies at all times the samerelative position to the stops, and produces an equal friction upon thestops, whatever may be the position -of the bolt.

The tumblers are all guided between the projections m, and have in theend of each alcop or spring,

on both sides of which the bits or wards of the key touch and act, thewidth ot' the' openings beingvequal to the length of the key-bits.

The tumblers c and el have slots in them, which, when brought oppositethe ends of the stops a b,.allow the key to force back the bolt, saidIstops entering said slots, so that, if the key also moves the tumbler jso that the stop e on the bolt can enter the opening in said tumbler,the bolt will be withdrawn or nn locked by the action of the key on thejaw h of the bolt.

Suppose, now, when the bolt is withdrawn or unlocked, another key, otherthan the one which last previously operated the lock, is introduced andturned in a direction to lock or throw ont the bolt, it follows, thestops a and b being engaged in the slots in the tumblers c and d, thatthe tirst eifect of turning the key will be to move said tumblers, andrearrange the stops by sliding them undcrthe frictional gripe by whichthey are held.

The continued rotative movement brings the tumblerj into proper relationto the stop e, and then the key, acting on the jaw h of the bolt, locksthe bolt or throws it outward, and a reverse turning movement given tothe key brings all the tumblers back to their proper relation to all thestops, and lets them enter the slots in the tnmblerswhen the keyoperates ou the jaw h of the bolt in unlocking or withdrawing it.

The springs n o`n the tumblers serve simply to throw them from theposit-ion in which the key sets them in locking and unlocking the bolt.

. It will now be seen that, it' the bolt and tumblers have been operatedby key, fig. 11, to produce the condition shown in iig. Il', key iig.12, or any other key in which the bits 1 2 are arranged differently iurelation to each other from what they are kin g. l1, will not place thetumblers c d in such relation to the stops a b as will permit the saidstops to enter thcslots in said tumblers.

The box-cover o is made with anges, p, which shut down over the iiangesof the lock-case q, making a rim-lock suited to be bolted upon thesurface of a door at its edge, by screws `passiugthrough the holes r,or, if a drawer-lock is needed,- the simple plate-cover s is screwed tothe lock-case.

By thus making the covers o and s interchangeable, 1` can easily adaptthe lock to either of two main uses, and thus produce two locks with butone set of tools and machinery.

The keys shown and described I term double-bitted,

because each bit l, 2, 85o., projects on both sides of friction-stops,and double statonary-bitted keys, subthe shank. I also term thekeys-stationary bit-ted, in stantially as and for the purpose described.

cotradstinetion to flouble-bitted keys, in which the Also, converting a.rim or mortise-lock into a. drawer bits are changeable or movable. orcabinet-lock, or vice versa', by changing the covers. What I claim as myinvention, mid desire to secure GHAS. C. DIGKERMAN. by Letters Patent,is

The friction spring fi, when secured on the bolt f by Witnesses: theadjusting-screw k, in combination with a lock J. B. CROSBY,

having one or more double-barred tumblers, movable FRANCIS GOULD.

